Packaged semiconductor devices generally comprise an integrated circuit (IC) die which is conventionally a silicon die that is mounted on a die pad of a workpiece such as a lead frame using a die attach adhesive. Other workpieces include an interposer, printed circuit board (PCB), and another IC die. For IC die assembled top (active) side up and back side down, the die attach adhesive provides a mechanical attachment, and generally also provides an electrical and/or thermal pathway to the die pad. The die attach adhesive generally comprises a polymer such as a polyimide or an epoxy-based adhesive. Silver is often added in particle flake form as a filler to raise both the electrical conductivity and the thermal conductivity of the polymer material.